The vote today in London was more than 99 percent in favor, said Chris Evans, a spokesman for the LME. The board backed the proposal June 15 after offers from rivals including CME Group Inc., Intercontinental Exchange Inc. and NYSE Euronext. The proposal needed the backing of more than 50 percent of shareholders and owners controlling at least 75 percent of the stock in the 135-year-old exchange.

Hong Kong Exchanges is buying a bourse handling more than 80 percent of world trade in industrial-metal futures, setting global prices for metals from copper to aluminum to nickel. It is the first overseas acquisition for the Asian bourse, the world’s second-biggest exchange by market value, and its first contracts in commodities. LME members may get more access to China, which consumes more metal than any other nation.

“This is now the beginning of something new for the exchange,” said Martin Abbott, chief executive officer of the LME. “What we’ve got now is even more resources and even more opportunity.”

$15.4 Trillion

Metals prices more than tripled in the past decade as demand from emerging markets overwhelmed supplies from mines. The LME, home to London’s last open-outcry trading, handled a record $15.4 trillion of contracts last year. Hong Kong Exchanges closed little changed at HK$101.60 ($13.09), leaving the shares down 30 percent since Feb. 18, when the South China Morning Post reported the bid.

The exchange is owned by LME Holdings Ltd., which issues two classes of stock. There are 12.9 million ordinary shares, which confer ownership and traded at 4.925 pounds ($7.65) last July, before the LME said it was considering bids. Hong Kong Exchanges offered 107.60 pounds a share. JPMorgan Chase & Co. and Goldman Sachs Group Inc. are the biggest investors, with closely held Metdist Ltd. the third largest, LME data show.

The bourse will continue to be regulated by the Financial Services Authority. Final approval is expected in November, Abbott said.